LEVELnews

Great Lakes–St. Lawrence River Water Levels
Volume 19, Number 8

11 August 2011

Water Levels Update and Meeting Reminder

Due to above-average water supplies and below-average outflows, the level of Lake Superior rose by 8 cm in July, compared to its average July increase of 5 cm. The level of Lakes Michigan–Huron ended July at the same level at which it started the month. As it happens, this is what it has done on average during the month of July over the 1918–2010 period of record. Lake St. Clair’s level fell by 2 cm last month, which is equal to the average amount it falls in July. The level of Lake Erie fell by 10 cm during July, which is twice its average decline of 5 cm for the month. Above-average outflows combined with below-average supplies caused Lake Ontario’s level to decline by 23 cm last month, compared to its average July decline of 8 cm.

With average water supply conditions, the level of Lake Superior is expected to rise by a few centimetres during August. The levels of lakes Michigan–Huron, St. Clair, Erie and Ontario are all expected to decline, as they typically do during the month of August.

Great Lakes Water Level Information
 July 2011 Monthly Mean LevelBeginning-of-August 2011 Level
LakeCompared to Monthly Average (19182010)Compared to One Year AgoCompared to Beginning-of-Month Average (19182010)Compared to One Year Ago
Superior26 cm below6 cm above25 cm below10 cm above
Michigan-Huron32 cm belowSame31 cm belowSame
St. Clair3 cm above12 cm above5 cm above10 cm above
Erie17 cm above21 cm above16 cm above18 cm above
Ontario15 cm above17 cm above7 cm above5 cm above

As mentioned in last month’s edition of LEVELnews, the International Lake Superior and St. Lawrence River Boards of Control are holding public information meetings during the evenings of Tuesday, August 30, and Tuesday, September 20, respectively. The formats of both events are the same: participation in person at a local meeting site or by telephone. There will be a brief discussion period from 6:45 to 7:00 p.m. at the local meeting sites for both events to determine local concerns. The respective Board presentations will then begin at 7:00 p.m. and will be heard by both meeting-site attendees and callers. Following the presentation, the floor will be opened for comments and questions from callers and attendees.

To participate in the Superior Board’s meeting by telephone, please call 1-866-551-3680 (toll free) between 6:45 and 6:55 p.m. on August 30 and enter the Participant PIN Code 9076483, followed by the # key on your telephone.

Participation in person is at the following meeting site:

Ontario and Michigan Rooms
Walker Cisler Student and Conference Center
Lake Superior
State University
650 West Easterday Avenue
Sault Ste. Marie, Michigan

Please visit the Superior Board’s website for additional information and to download the meeting materials. Any updates will be posted on August 26 on this website.

To participate in the St. Lawrence River Board’s meeting by telephone, please call 1-877-413-4814 (toll free) between 6:45 and 6:55 p.m. on September 20, and enter either of the following two access codes:
8225560 for English or
7333134 for French;
or mention “St. Lawrence Control Board” to the operator.

Attending the St. Lawrence Board’s meeting in person can be done at either of the following two meeting sites:

St. Lawrence Room West
Ramada Inn
805 Brookdale Avenue
Cornwall, Ontario

or

Room 118 of Rich Hall
SUNY Oswego
Oswego, New York

Please visit the St. Lawrence Board’s website for more information and to download the meeting materials. Any updates will be posted by September 16 on this website.

July Precipitation over the Great Lakes*
Great Lakes Basin92%Lake Erie115%
Lake Superior84%(including Lake St. Clair)
Lakes Michigan-Huron 93%Lake Ontario78%
July Outflows from the Great Lakes*
Lake Superior76%Lake Erie104%
Lake Huron91%Lake Ontario114%

*As a percentage of the long-term July average.
NOTE: These figures are preliminary.